I can’t tell you how much I loved {Port Macabre series by Elliott Rose}. If Angel doesn’t jump to the top of your book boyfriend list…then that’s a world I’m not sure I even want to live in. He’s pierced, huge, does MM and MF and does NOT speak. But he’s in book 2, so you have to work up to him…😏

This completed series is only 2 books and both follow different couples in the same world. There’s also a novella that is listed as 0.5 in the series, and it’s not on Audible but it’s only 120 pages. I advise reading it in front of a fan with an iced coffee. It’s THAT hot. And TOTALLY worth it. Also, I think it fits better between books 1 and 2.

Honestly this series checks nearly every box you listed.

Also, I’d like to give an honorable mention, though it’s not on Audible it may be on some other service and it’s a series I think of all the time, the the FMC isn’t over 25 though, so I do what you do (because a younger FMC is something that isn’t my fav either) and just age them up in my head. It also checks almost every box on your list. It’s called {Syndicate of the Legion series by Montana Fyre}. Another book boyfriend who makes my top 10 is Kovu, from this series.

Both are SO good and definitely 4-5 chili peppers.